The great rice heater experiment

2010-10-06 - Conclusions: It appears that the rice did raise the temperatures slightly, although I do not believe that the small amount that it raised the temperature would do much good. I am leery of adding much more than I already have. I know that people have had over heating issues with rice and I wonder what the starting temps were when the rice was added. At the low temps we have had lately (compost was in the high 60's), I am of the belief that the bacteria, that usually cause the heat issues, didn't have ideal conditions to explode with growth. If this were the case, then the only time that greater amounts of heat would be generated would be those times when it was not desired. At this point I will be using some Christmas lights in the bottom of the flow through. I can control them a little easier. I am hopeful that the heat will rise and the worms will shy away from the light and migrate up ... where they are supposed to be. Sometimes I wonder if I shouldn't have painted arrows on the inside of the bin instructing them which way to go :-).

2010-09-30 - With no noticable change in the difference of ambient vs. compost temprature min/max values, I decided to place a little more rice in the bin. The picture is below at the bottom of the post.

2010-09-24 - Updated below with daily baseline temp readings and picture of rice dispersal pattern. Note: I increased the amount of rice slightly from piles of 4 grains to piles of 8-10 grains.

I looked through the history of the posts but didn’t see up with anything like this, so if anyone knows if this has been done before, let me know so that I don’t reinvent the wheel.

With winter coming, I’d like to perform a very controlled experiment using rice to heatmy FT worm bin. We are having cool days (lows around 50 F highs around 65-70F) and I thought now might be a good time to experiment. I plan on getting daily temp differences between the bin’s ambient air temp and a sensor buried in the compost. I have the ability to see the high and low for the day. I will collect this information daily. After 4 or 5 days I plan on adding rice to the right 1/3 of the bin (plenty of safety room for the worms to flee).

I was thinking about placing 8 10 piles of 4 8 to 10 grains of cooked white rice evenly dispersed along the right 1/3 of the bin near the other food (under the shredded paper/leaves) and then checking the daily temps for the next 4 to 5 days to see if the difference between ambient and compost temp difference has changed.

If after a week there are no differences I will look for any residual rice, remove it if possible, and try again by adding 8 piles of 16 to 20 grains of rice in the same locations... and so on.

I’d like to acquire the following information from the experiment:

How much rice does it take to produce heat?

How much heat does rice produce?

How long will the heating effect last?

I plan on adding the results to this blog entry (unless some provides me with results from a similar experiment thus saving me the work).

Thanks

Baseline Readings

Day

Ambient Temp

Compost Temp

Difference

Low

High

Low

High

Low

Hi

1

50

86

55

83

5

3

2

68

81

71

78

3

3

3

65

81

71

79

6

2

4

65

81

71

77

6

4

5

52

63

58

66

6

-3

Added rice mid-day. You can see the 10 small piles of 8-10 grains of cooked white rice on top of about 2.5 lbs of cut up rotten apples that have been frozen and thawed.Temperature probe is buried just below the right hand side of image. I then covered with a single sheet of newspaper and added shredded paper to the top of that and recovered with the burlap.

Larry S., a few of us have tried heating experiments with rice, beans & bread, but I don't think any of us documented it the way you're planning to. Sorry, but I think you'll just have to "do the work". :-) I'm fairly certain that it will take more than a few grains of rice. I was going to try it again when it got cooler, but I was going to start with at least a cup or two of cooked rice. Larry D. probably did the most recent experiment (it might've been an accident), but I don't know if he measured the amount of rice that he added.

It looks like you're getting some difference with the rice heating on days 12 and 13 at least. If this keeps up. I think you're going to need a greater quantity of rice to see much difference, but starting small is really smart. I never start small and have overheated my bin a couple of times. I'm impressed with your work. Keep the data coming!